The present invention relates generally to means for retaining a wheel trim member in operative relationship to a vehicle wheel and more specifically to such retention means which are uniquely adapted for use with wheel trim members fabricated from a plastic composition.
Wheel trim in various forms have long been employed on motor vehicles both for the purpose of protecting the vehicle wheel as well as providing a decorative aesthetically pleasing appearance thereto. One of the major problems associated with such wheel trim has been to design reliable and inexpensive retention means which will securely retain the wheel trim to the vehicle wheel while still allowing it to be easily removed so as to enable the vehicle wheel to be removed from the vehicle. In use, wheels are subject to extreme environments and a great variety of vibrations and other forces which the retention means must be able to withstand and yet still allow the trim to be easily removed. Compounding this problem is the desire to keep the cost of the wheel trim as low as possible, to minimize interference with the aesthetic design of the trim, and to prevent annoying rattling or relative rotation of the wheel and its trim member. These problems are particularly difficult to overcome when a plastic composition material is used to fabricate the wheel trim as the plastic material is not well suited for resisting localized retention stresses generated by conventional retention systems particularly under such adverse conditions as are encountered by the vehicle wheel such as the temperature extremes and other climatic variations.
A wide variety of retention means have been developed in an attempt to satisfactorily resolve this problem both as applied to plastic wheel trim members and such wheel trim fabricated from various types of metals. In one common arrangement, a retention band is provided which has a plurality of retention clips secured thereto which are adapted to engage a portion of the vehicle wheel. Typically, the retention band is secured to the wheel trim at the outer peripheral edge thereof by crimping a portion of the wheel trim thereover. The retention band may also have an inner edge secured to another portion of the wheel trim member. However, this type of an arrangement while possibly producing satisfactory results for a wheel trim member fabricated from a metal material, is less than completely satisfactory when applied to a plastic material as the total retention stress is concentrated at either the outer peripheral area of attachment of the retention band to the wheel trim or merely divided between the inner and outer points of attachment. Various other arrangements are also provided where variously shaped clips may be attached directly to a portion of the wheel trim member or a retention band-like portion integrally formed with the wheel trim member.
A common problem presented by these various configurations is that there exist a rigid connection between the wheel trim member and the clip or retention band means thus allowing various vibrational forces encountered by the wheel to be transmitted directly through the engagement between the vehicle wheel and the clip to the wheel trim member. When the wheel trim member is fabricated from a plastic composition, the continuous subjecting thereof to such vibrations may cause breaking or other deterioration within a relatively short period of time particularly during periods of low temperature.
Accordingly, the present invention provides an improved wheel trim retention means particularly adapted for use with wheel trim fabricated from plastic compositions which is designed to minimize the transmission of wheel originating vibrations to the trim member while still securely and removably retaining the wheel trim in position on the vehicle wheel. Also, the retention force exerted by the present invention is directly dependent upon the strength of the biasing means associated therewith and therefore may be easily varied between different wheel trim members so as to facilitate retention means cost optimization for each type of wheel trim while still achieving the advantage of a standardized clip member. Further, the retention means of the present invention eliminates the need for a retention band which bands were typically fabricated from a metal material thus allowing for reduction of the overall weight of the wheel trim member. This weight reduction is extremely important particularly in view of the pressing governmental demands to reduce vehicle gasoline consumption. Further, as the weight of the wheel trim member represents unsprung weight, it has a significant effect upon ride performance of the vehicle as well as the required strength of the various suspension components. Also, the retention clip of the present invention may be easily removed and replaced as may the biasing means associated therewith thus enabling a vehicle owner to easily repair the wheel trim member in the event a portion of the retention means provided thereon becomes broken.
Additional advantages and features of the present invention will become apparent from the subsequent description taken in conjunction with the claims and drawings appended hereto.